French patent specification No. 2415563 discloses an arrangement of a screen wiper in which the bushes of the insert piece are fitted in bores or holes which are formed in each of the said first and second elements.
The specification of French published patent application FR 2443949A discloses another arrangement of a screen wiper in which, in order that the insert piece can be arranged between the U-shaped channel portion of the first element and a corresponding U-shaped channel portion of the second element, it is arranged that two of the bushes, which constitute inner bushes, are first fitted into the bores or holes which are formed in the second element, and the side walls of the first element are then moved apart in such a way that the other, or outer bushes of the insert piece can then penetrate into the holes or bores which are formed in the side walls of the first element.
This latter arrangement involves some complication in the operation of fitting the two elements, because it is necessary to increase the distance between the two side walls of the first element, and then to bring the two walls into a desired spaced relationship. In addition, during this operation, it can happen that the two side walls will be taken beyond the desired spacing, which can result in an undesirable deformation of the insert piece. This is detrimental to proper subsequent operation of the articulation between the first and second elements of the swinging linkage.